Tenderizing meats



Patented Aug. 22, 1950 2',519;931 TENDERIZING MEATS Harry L. Roschen, Maywood -and Bernard J. ()rtscheid' and John M.J.RamSbottom, Chicago,

111., assignors, by mesne assignments, to Swift & Company, a corporation of Illinois 'No Drawing. Application February 8, 1947, .Serial No. 727308 7 Claims.

"This invention relates in general =to' a*'process wof treating edible animal carcasses andacuts thereof and more particularly to a process1of accelerating the rigor mortis transition period in the saidcarcasses and cutsthereof.

it has beencustomary in thecommercial processing of carcasses and cuts thereof to remove the skin'from the carcasses relatively soon after '-"slaughtering--and to transfer the cleaned carcasses tc-a --cooler=wherein the temperature maybe lowered-to around 'freezingandsometimes substantially below freezing. .During this storage period which may extend from two to three weeks, the

carcass ages or beeemesmore'tender and :acceptable to the trade.

It has recently been discovered that the aging of animal carcasses and cuts thereof' does not ebegin tohave any 'tenderizing eifect until" after -l;hei':carcasses have passed through the condition pommonly -known as rigor mortis. "Under normal "conditions or handling: rigor mortis changes are not complete until 16 to -2' l'hours =after-slaughter- -ing. Moreover, during'the prolonged period .of rigor mortis there is evidence of an apparent toughening of the meat which must be overcome- "during the subsequent aging process.

Because this aging process is' very-timeconshining-numerous methods of treating carcasses "have-been devised where'inthe skinned carcass ee'ither in the frozenor chilled condition is subjecte'd to internal or 'externalheat' until the desired: result -is obtained. These processes howeven arepbjectionable in certain respects because they either employ elevated temperatures whicli mouse unwanted colorchanges to'take place, or ethey employ temperatures which are so low 1 that they -fail to accelerate the aging processtorany appreciable degree.

An object of I the present" invention is toacc'el- -0erate -the rigor mortis transition-periodin the "carcasses and "cuts thereof whereb ;aanimal'rcarcasses so that the rigor .mortistransitionperiod transpires in a veryshortitimez'with- -ment.

-'An additional object of the invention is to :maintain the carcasses under such conditions that themeat may besubsequently tenderized in anon methods.

outi mploying special heating or handlingequiprelatively hort time and by 'normalrefrigera :St'ill other objects of this invention will become @apparent' from the description and claims to follow.

:Accordingto the .present invention animal carcasses .of beef, lamb, veal, or the like may be brought through the condition commonly known as rigor mortis in a relatively short time by main- *taining the freshly slaughtered carcass at the mormalibody temperaturerof the animaliforra few hcursammediately: after slaughtering said animal eand beforeaanyaof themormal body heat "of the animal dissipates.

.iini thez:preferredxembodiment .of the invention the whole beef carcass tis:v skinned on the killing *fioor andlimmediatelyplaced in a chamber hav- .ingaapproximatelya'FQO Lper centrrelative humidity iand :heldiat' 'a temperature of approximately .9826"v .After-athez carcass has been maintained at the; said temperature for approximatelyA to'35 ahours'zrigor't'mortis is complete :and thezcarcass is then-tehilled: to stcrage temper-atur es, approximately 34 F.

According to another modification of .the'in- "-yentionza freshlyyskinned lamb carcass is wrap- .ped' With 'al br-ine. moistened cloth before any: appreciable. amount of the heatpresent has-dissipated 'a-ndnimmediately placed in the treating chambenmaintained at a temperature 10f ap- ;;-proximately 100:F. After approximately 3ihours :in said chamber rigormortis substantially complete :andthe carcass is chilled to1around-34 @F; for-:normal holding and aging. e-As another example of. the :inventiona round freshly dressed veal carcasswith the hide on is placed yerysaoiraiter the slaughtering in a i treating achamber having a temperature of approximately 99 F. After a:zperiod-..of approximately 4 hours in said chamber rigor mortis is substantially complete and thecarcass is chilled to normal holding and aging temperatures, approximately 34 F.

In each of the foregoing examples it will be observed that the temperature at which .the treating chamber is maintained is substantially the 'normal body temperature of the animal. These body'temperatures may vary slightly but generally-are-between98"Fvand "100 F. "It is important that the temperature of 1 the treating chamber 'does' not rise'mate'rially above the nor- "mal 'boly temperature of the 1 animal. If temperaturesmaterially' above the' body temperature of the-animal are employed in the treating chamberobjectionable color changes in the-meat are 'observed. Likewise "in each-of the-above ex- :amplesit will baobserved that the-animalcarcass 3 is processed immediately or soon after slaughtering and before there is any appreciable drop in the temperature of the carcass. By processing in the foregoing manner the rigor mortis transition 4 muscle of the beef carcass and without further treatment placed in the above chamber. Tenderness comparisons were then made between the test and control samples after holding and aging period is greatly accelerated and the toughening 5 each for the specified periods.

Table II Tenderness RatingBeei Held at 98 F. for 4 hrs. vs. Control Samples 1 Day Rating 3 to 4 Day Rating 6 Day Rating Initial ve. Readin Adv. for Adv. for Adv. for

g Ave. Difl. Test Ave. Diff. Test Ave Din. Tm

Test #1. +3.0 T 3. 0 5.0 +2.0 5. 5 +2. 5

C 5.7 4.2 1.5 5.6 0.1 Test #2.

C 3.7 3.0 0.7 6.1 +1.4 Test #3.

C 2. 8 4. 0 +1.2 6. 3 +3. 5 Test #4.

C 5.3 3. 7 1. 6 7.3 +2.0 Test #5.

C 4. 3 3: 6 0. 7 5.6 +1.3 Test #6- of the meat which generally accompanies rigor mortis is substantially avoided. Thus the sub-' sequent aging period may be greatly shortened when this invention is practiced.

While it is unnecessary to maintain the humidity of the treating chamber at a high degree in every instance, it is preferable to maintain the 5 measured by its pH, changes gradually after 7 slaughtering. Under normal conditions, the pH value one or two hours after slaughtering is about 6.5 to 6.6, whereas the final pH value after rigor mortis is complete falls between 5.4 and 5.8 and remains substantially constant throughout the normal holding and aging of the meat.

The data presented in Table I represents the changes in pH values which were observed when a number of longissimus dorsi muscles from the ribs and loins of several freshly slaughtered beef carcasses were held at approximately 98 F. for

the specified times:

Table I .pH values Time in hours 0 1 hr. 2 hr. 3 hi. 4 hr. 5 hr. 6 hr. 1 111'.

Test #1 6.2 5. 9 5. 6 5. 5 5. 5 5. 5 5. 5 Test #2 6. 2 5.9 5. 6 5.4 5.4 Test #3 6.3 5.7 5.6 5.4 5.4

As shown by the above data the meat cuts at I the end of a period of between 3 to 5 hours have substantially passed through rigor mortis.

The data presented in Table II represents the' results obtained when a number of beef longissimus dorsi muscles were held at approximately 98 F. for a period of 4 hours and then placed in .a chamber maintained at 36 F. In each of the tests control samples were taken from the same In Table II the tenderness of the cuts was rated on a scale of from 10 to l with 10 being excellent, 1 being extremely poor, and any rating above 5 being satisfactory. It will be observed that the improvement shown by the test samples over the control samples is the net diiference in the ratings at the end of any given period over the original ratings.

The data shown in Table 11 indicate that there is generally an appreciable gain in tenderness of the treated samples over the control samples.

This gain is especially marked in the early stages of the aging period and is of commercial significance since the eifect obtained in the ordinary aging practice can be obtained several days earlier by using the present invention.

The temperatures and humidity specified herein may be obtained and maintained in any desired or suitable manner such as, for example, by steam injection, by brine, or water spray, etc.

.As described the present invention has the advantage of shortening the required aging period by accelerating the process of rigor mortis without employing special equipment or apparatus and without causing objectionable color changes in the meat.

The term animal carcass as used in the claims is intended to include the whole animal body after slaughtering and parts thereof into which the body is commonly divided in commercial slaughter house operations.

Obviously, many modifications and variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

1 "WeClaim:

. l. A process of treating animal carcasses and cuts thereof to accelerate the rigor mortis transition period without causing any appreciable color changes in the carcasses and cuts thereof, which comprises placing a freshly slaughtered carcass in a treating zone maintained at a temperature approximately that of the normal body temperature of the animal before an appreciable amount of the normal body heat of the said animal has dissipated therefrom, maintaining the said carcass in the said Zone at the said temperature for a period of at least between ap proximately 3 to 5 hours, and then chilling the treated product to normal holding and aging temperature.

2. A process of treating beef carcasses and cuts thereof to accelerate the rigor mortis transition period without causing any appreciable color change in the carcasses and cuts thereof, which comprises placing a freshly slaughtered carcass in a treating zone maintained at a temperature approximately that of the normal body temperature of the animal before an appreciable amount of the normal body heat of the said animal has dissipated therefrom, maintaining said carcass in the said zone at said temperature until the pH value of the carcasses is between approximately 5.4 and 5.8, and then chilling the treated product to normal holding and aging temperature.

3. A process of treating animal carcasses and cuts thereof, comprising placing a freshly slaughtered carcass in a humidified treating zone maintained at a temperature of about the normal body temperature of the animals for a period of at least between approximately 3 to 5 hours before an appreciable amount of the normal body heat of the said animal has dissipated, whereby rigor mortis is substantially completed, and then chilling the treated product.

4. A process of treating animal carcasses and cuts thereof, comprising placing a freshly slaughtered carcass in a treating zone maintained at a relative humidity of approximately 90 per cent and a temperature of from between 98 and 100 F. before any appreciable amount of the body heat of the said animal has dissipated therefrom, maintaining the said carcasses and cuts thereof in the said zone at the said temperature for a period of at least between approximately 3 to 5 hours whereby rigor mortis is substantially completed, and then chilling the treated product.

5. A process of treating beef carcasses and cuts thereof to accelerate the rigor mortis transition period and thereby shortening the aging period required for tenderizing said carcass without causing any appreciable color change in the said carcass and cuts thereof, which comprises: placing a freshly slaughtered beef carcass in a treating zone maintained at a temperature approximately 98 F. and a relative humidity of at least approximately percent before an appreciable amount of the normal body heat of the carcass has dissipated therefrom; maintaining the said carcass in the said zone at the said temperature for a period of at least approximately 4 hours; and chilling the treated product to the normal holding and aging temperature.

6. A process for treating lamb carcasses and cuts thereof to accelerate the rigor mortis transition period and thereby shortening the aging period required for tenderizing said carcass with out causing any appreciable color change in the said carcass and cuts thereof, which comprises: placing a freshly slaughtered lamb carcass in a treating zone maintained at a temperature approximately F. and a relative humidity of at least approximately 90 percent before an appreciable amount of the normal body heat of the carcass has dissipated therefrom; maintaining the said carcass in the said zone at the said temperature for a period of at least approximately 4 hours; and chilling the treated product to the normal holding and aging temperature.

7. A process for treating veal carcasses and cuts thereof to accelerate the rigor mortis transition period and thereby shortening the aging period required for tenderizing said carcass without causing any appreciable color change in the said carcass and cuts thereof, which comprises: placing a freshly slaughtered veal carcass in a treating zone maintained at a temperature approximately 99 F. and a relative humidity of at least approximately 90 percent before an appreciable amount of the normal body heat of the carcass has dissipated therefrom; maintaining the said carcass in the said zone at the said temperature for a period of at least approximately 4 hours; and chilling the treated product to the normal holding and aging temperature.

HARRY L. ROBSCHEN. BERNARD J. ORTSCHEID. JOHN M. RAMSBOTTOM.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,169,081 James Aug. 8, 1939 2,388,891 Williams et al Nov. 13, 1945 2,419,119 Christensen Apr. 15, 1947 

1. A PROCESS OF TREATING ANIMAL CARCASSES AND CUTS THEREOF TO ACCELERATE THE RIGOR MORTIS TRANSITION PERIOD WITHOUT CAUSING ANY APPRECIABLE COLOR CHANGES IN THE CARCASSES AND CUTS THEREOF, WHICH COMPRISES PLACING A FRESHLY SLAUGHTERED CARCASS IN A TREATING ZONE MAINTAINED AT A TEMPERATURE APPROXIMATELY THAT OF THE NORMAL BODY TEMPERATURE OF THE ANIMAL BEFORE AN APPRECIABLE AMOUNT OF THE NORMAL BODY HEAT OF THE SAID ANIMAL HAS DISSIPATED THEREFROM, MAINTAINING THE SAID CARCASS IN THE SAID ZONE AT THE SAID TEMPERATURE FOR A PERIOD OF AT LEAST BETWEEN APPROXIMATELY 3 TO 5 HOURS, AND THEN CHILLING THE TREATED PRODUCT TO NORMAL HOLDING AND AGING TEMPERATURE. 